Here's what the U.S. Federal Trade Commission says about receiving packages you didn't order [1]:
"What do you do when you receive merchandise that you didn’t order? According to the Federal Trade Commission, you don’t have to pay for it. Federal laws prohibit mailing unordered merchandise to consumers and then demanding payment."
There is obvious nuance here [2]. Maybe receiving "stolen property" for example. But if the item is addressed to you, and you didn't order it, I think you're in the clear, and certainly nobody can demand payment and enforce it.
-edit-
This reminds me of the scams in Europe where someone will grab your hand and put a bracelet on or put a flower in your hair or something and demand payment. I've been in this scenario. All you have to do is walk away or just throw the merchandise on the ground. They'll change their tune quickly.
[1] https://www.consumer.ftc.gov/articles/0181-unordered-merchan...
[2] I'm not a lawyer.